Bay Area stays prepared for possible tsunamis

March 25, 2013 9:18:20 PM PDT

SAN FRANCISCO --

The devastating earthquake and tsunami that struck Japan happened two years ago this month. Experts say it's only a matter of time before a big one hits California. This is Tsunami Awareness Week and experts are watching around the clock for the one that could be coming our way.

Tsunamis in the south Pacific and Japan have shown the destruction that can come from powerful earthquakes in the ocean. Ships and cars tossed as if they were toys, and buildings ripped from their foundations and pulled into the sea. Hundreds of thousands dead and survivors left with no place to go.

But tsunamis don't just happen in the far Pacific, they happen on the West Coast too.

In 1964, a devastating tsunami struck Crescent City without warning. Almost 50-years later another one hit the same harbor, only this time locals knew it was coming.

"What the center does is it monitors all the earthquakes on the planet, 24-7, and it issues tsunami warnings if those warnings are large enough to warrant concern," Cindi Preller, with the NOAA West Coast Tsunami Center said.

The center analyzes the magnitude of earthquakes and collects data from buoys in the pacific to see if a tsunami is heading our way.

"California could easily experience a damaging local tsunami with anything from a 7 to above and then your far field threat is from the Pacific Rim, including the Alaska trench, Japan, Russia, the south Pacific, Chile even," Preller said.

The threat is real. If a tsunami hit the Bay Area, airports would possibly have to close, ports could shut down, homes would have to be evacuated. Inland, streams and rivers could flood.

In 2011, Santa Cruz Harbor was warned about the Japanese tsunami. That saved lives but did not prevent millions of dollars in damage.

An even larger tsunami could devastate the heart of the beach town.

"Some of the modeling has specifically looked at Santa Cruz, indicate the maximum height of a tsunami could be 25-30 feet," Logan Johnson, of the National Weather Service, said.

The National Weather Service office in Monterey is responsible for relaying tsunami warnings to Bay Area.

"We're looking at a turnaround time from the time of the earthquake, to the time of issuing a warning of on the order of 10 minutes or less," Johnson said.

In San Francisco, air sirens will sound and like many other low-lying cities, signs warn of the tsunami danger and how to get away from them.

"Once you get the warning you don't have a lot of time to decide exactly what you are going to do, so that's why we do the planning for it," San Francisco Department of Emergency Management spokesperson Rob Dudgeon said.

San Francisco could be hit by a tsunami on three sides. From Ocean Beach, from Crissy Field and the Marina District, even the Financial District could be flooded. For that reason, emergency services review their tsunami plan every year.

"You can plan for the maximum all the time, and nature will still blow that completely out of the water," Dudgeon said.

Experts say the best way to escape a tsunami is to get away from the water and head for higher ground.